Vegetables such as Chinese cabbage, spinach and celery have higher iodine content.

Animals contain more iodine than plants; The iodine content of seafood is higher than that of land products. The foods with the highest iodine content are seafood, such as kelp, laver, fresh hairtail, dried clam, dried scallop, mussel, sea cucumber, jellyfish, lobster, etc. Kelp has the highest iodine content.